Method for making a yarn package



3,054,9li Patented Nov. 20, 1962 3,064,911 METHGD FUR MAKING A YARN PACKAGE Joseph A. Truitt, Wallingt'ord,-Pa., and Charles L. Hansel,

Wilmington, Del, assrgnors to American Viscose (lorporation, Philadelphia, Pa., a corporation of Delaware No Drawing. Filed Sept. 9, 1960, tier. No. 54,844

6 Claims. (Cl. 24218) This invention relates to a method for making a yarn package.

Certain yarns, particularly zero or low twist filament yarns used for sewing, present a problem in packaging. Excessive shelling or shedding of the yarn layers from the package occurs in shipping and in use unless relatively costly expedients are undertaken to avoid the problem. With yarn of this type, sloughing off or shelling is experienced in all of the various types of yarn packaging such as cone, tube, bobbin, cake and cheese packages.

Various methods for solving this problem were tried.

For example, tacky or wax-type finishes have been applied to the yarn prior to winding to prevent shelling; however, when a sufiicient tackiness was obtained to prevent shelling, the increase in yarn-to-metal friction experienced was detrimental to the use of yarn for machine sewing.

Pressure sensitive tape was applied to the yarn package to keep it from shelling during shipment; however, removal of the tape from the cone presented additional problems and bits of adhesive remaining on the yarn interfered with machine sewing operations.

An oversized sheet of stiff cellophane was used to wrap the yarn package. Contrary to usual practice, the wrapper remained on the package during use, its oversized top being open into a funnel-like shape to assist in controlling shelling and permit withdrawal of the yarn. This procedure was only moderately successful in preventing shelling and caused additional disposal costs.

Cohesive additives were added to the yarn finish prior to winding; however, the additives used did not prevent shelling unless the yarn was kept moist during winding and this proved to be commercially impractical.

Addition of a twist to the yarn will help prevent shelling but this procedure is costly and requires reconing into a sale package.

It is an object of this invention to provide an inexpensive method for the preparation of a non-shelling yarn package wherein desirable machine sewing characteristics of the yarn are maintained.

In accordance with this invention the improved yarn packa e comprises a yarn wound into a tight package, and from about 0.5 to about by weight based on the yarn of a water-soluble, film-forming material impregnating said yarn and binding adjacent yarn windings of said yarn packa e.

The method of this invention comp-rises impregnating unwound yarn with an aqueous medium containin from about 0.5 to about 10% by Weight of a water-soluble, film-forming material, drying the yarn, windin said yarn into a tight package, immersing the packa e in water for from about 2 seconds up to about 2 minutes, and drying the package.

The film-forming material which is suitable for this invention includes, for example, water-soluble vinyl polymers including polyvinyl alcohol, polyvinyl esters which have been completely or almost completely hydrolyzed, polyvinyl formals, polyinvyl pyrrolidone, alkylene oxide modified polyvinyl alcohol; water-soluble alkyd resins; albumen; carbohydrates and carbohydrate esters and ethers.

Of the above water-soluble film formers, polyvinyl alcohol and polyvinyl pyrrolidone are preferred on the basis of availability, cost and performance in producing a non-shelling package While maintaining the desirable sewing properties of the yarn. The vinyl resins generally employed have average molecular weights ranging from about 10,000 to 100,000 and preferably from 20,000 to 60,000. The film formers are dissolved in the aqueous medium to obtain a concentration of from about 0.5 to about 10% by weight. With the use of polyvinyl alcohol for zero twist sewing yarn a concentration of about 3% is preferred while about 1.5% is preferred for polyvinyl pyrrolidone.

Under the above described concentration conditions, from about 0.05% to about 10% of the film-former, based on the weight of the yarn, will be incorporated in and on the yarn.

Water-soluble film formers, and in particular, polyvinyl alcohol, have been used in the past as components of yarn finishes and as coatings for yarns wound into packages; however, it is entirely unexpected that a nonshelling package of yarn retaining excellent yarn-to-yarn and yarn-tometal frictional properties could be produced with this material and in this manner.

The winding of wet or damp yarn containing an aqueous solution of film-forming material to form a non-shelling package with yarn of good sewing properties is not commercially feasible since a higher concentration of film-former is required, drying control becomes critical, poor package formation occurs, and machine sewing characteristics of the yarn are not satisfactory.

Immersion of the yarn package into an aqueous solution of film-forming material will produce a non-shelling package. However, to obtain the desired machine sewing yarn characteristics and for a practical plant scale procedure, the method described for this invention is much preferred.

in accordance with the method or" this invention it is most desirable that the densely wound yarn package be completely immersed in water for a minimum of 5 seconds to a maximum of 20 seconds, and with conventional tube or cone wound zero twist rayon yarn packages of the industry, a 10 second immersion time has been found to be most satisfactory to obtain the desired bonding result without efiecting the yarn sewing characteristics. The size of the yarn package is not critical while the particular film-forming material used may require additional immersion time within the prescribed general limits to obtain the best result. Self-sealing or bonding is assisted by the swelling of the moistened yarn which tends to contract lengthwise but cannot do so by reason of the solid mass below it. This produces increased pressure on the outer layers at each crossover point of spirally wound yarn packages resulting in a stronger bond than if the package is wound with wet or damp yarn.

It has also been found that the temperature of the water into which the package is immersed should be between about 50 and about F. since higher water temperatures and longer immersion time necessitated by lower water temperatures tend to remove the film-forming materials and thus are not desirable.

Any convenient means for immersing a plurality of packages uniformly as to time, temperature and axial position, for example, submerging conveyor or tray dipping, is suitable for the preparation of the yarn package of this invention.

For best results, the excess water should be permitted to drain from the yarn package for a short time in still air. After the excess surface fluid has drained, the package is preferably wrapped in water vapor retardant sheet material such as wax paper, glassine, coated cellophane or the like. This helps to produce a more uniform inward penetration of the water into the layers of the yarn package; thus the wicking action of the fiber produces a more uniform sealing action.

Other non-film-forming yarn finishing agents are usually present in the aqueous film-forming solution through which the yarn is run prior to drying and winding. These agents include, for example, fatty acid esters of mono hydric alcohols, e.g., butyl stearate; fatty acid esters of polyhydric alcohols, e.g., glyceryl stearates; and polyoxyalkylene derivatives of fatty acid esters of polyhydric alcohols, e.g., polyoxyethylene glyceryl monostearate. They are usually present in amounts of up to 2 percent.

The following example is set forth to demonstrate the method of this invention.

EXAMPLE An 1100 denier yarn was run through a finish bath comprising an aqueous solution containing 1.5% by weight of polyoxyethylene glyceryl monostearate, 1.5% by weight of butyl stearate and 3% by weight of polyvinyl alcohol. The yarn was immersed in the bath for a distance of about 15 inches at traveling speed of 50 meters per minute. It was then run through a drye. and dried to a moisture content of 4 to 5%. This driedfinished yarn was then spirally wound on a 7 inch tube having a diameter of 2 /2 inches with a rapid traversing aid to obtain a standard yarn package weighing 10 pounds. This package Was completely immersed in soft water having a temperature of about 65 F. for a period of 10 seconds. The package was permitted to drain in a vertical position for 2 minutes and then wrapped in moistureproof paper to dry for to 24 hours prior to shipment. The package proved to be completely satisfactory from both the shelling and sewing standpoints.

The method of this invention and the package produced thereby have solved a serious commercial problem in this field. The method does not add materially to the cost of production and eliminates labor and related costs required to add a number of twists per inch to the yarn.

Various changes and modifications may be made in practicing the invention without departing from the spirit and scope thereof and, therefore, the invention is not to be limited except as defined in the appended claims.

We claim:

1. A method of making a yarn package which comprises impregnating unwound yarn with an aqueous medium containing from about 0.5 to about 10% by weight of a Water-soluble, film-forming material, drying the yarn, winding said yarn into a tight package, immersing the package in water for from about 2 seconds up to about 2 minutes, and drying the package.

2. A method of making a yarn package which comprises impregnating unwound yarn with an aqueous medium containing from about 1 to 3% by Weight of a watersoluble vinyl resin, drying the yarn, winding said yarn into a tight package, immersing the package in water for from about 5 seconds up to about 20 seconds, and drying the package.

3. The method of claim 2 wherein the vinyl resin is polyvinyl alcohol.

4. The method of claim 2 wherein the vinyl resin is polyvinyl pyrrolidone.

5. A method for making a yarn package which comprises impregnating unwound zero twist rayon yarn with an aqueous medium containing from about 1 to about 3% by weight of a polyvinyl alcohol, drying the yarn, winding said yarn upon a bobbin into a tight package, immersing the package in Water for from about 5 seconds to about 20 seconds, draining excess fluid from the package, and then immediately enclosing said package in a moistureproof sheet.

6. The method of claim 5 wherein the aqueous medium contains up to about 2% of butyl stearate and up to about 2% of a polyoxyethylene derivative of glyceryl monostearate.

References Cited in the file of this patent UNITED STATES PATENTS 2,035,930 Strong Mar. 31, 1936 2,101,282 Piper Dec. 7, 1937 2,594,521 Tingley Apr. 29, 1952 2,674,215 Thompson et a1 Apr. 6, 1954 

